Remove starfire support
Starfire (aka E10K) is 2 decades old, and we know of nobody who has access to such a system, so we have no way to test it, and it's regarded as unlikely that illumos would work. (A dedicated, closed System Service Processor is required in any case.)
Rather than carrying around code we cannot test, cannot use, and therefore cannot fix, we should remove support for this platform.
This is mostly kernel/platform support, but there are also bits in userland (such as parts of cvc).